When Austan Goolsbee leaves this fall as head of the Council of Economic Advisers, President Barack Obama will have a chance to replace him with the type of person who hasn’t yet held the post: a moderate.

Obama’s earliest economic advisers — liberals Goolsbee and Christina Romer — pushed for major initiatives like the health care overhaul, financial reform and the stimulus. His new CEA chief is likely to assume a more defensive role, countering Republican attacks on those policies.

After the first two years of a president’s term, “things do slow down, but I think it’s got to be even more so, given the outcome of the last election and how aggressive the Republicans have been,” said Dean Baker, the co-director of the left-leaning Center for Economic and Policy Research.

For that reason, it might make sense for Obama to favor a moderate over a liberal as his next top economic adviser — especially, Baker said, if deficit reduction is a recurring theme.

Two possible candidates were described by their allies as ideal fits for the position because of their willingness to give credence to both sides of economic issues. They are Rebecca Blank, a Commerce Department economist whom Obama has reportedly interviewed for the post, and Alan Auerbach, a professor at the University of California at Berkeley.

“I think the president certainly needs someone who is capable of seeing the best in … a variety of viewpoints,” said Aaron Edlin, a Berkeley professor who works with Auerbach, calling him a “moderate” and “open-minded.” “So I do think that someone who is moderate and balanced is a very good choice for head of the CEA. There are enough partisans in Washington. I don’t see that one needs another one as head of the CEA.”

Ron Haskins, a former Republican congressional adviser who worked with Blank on poverty in the 1990s, described her as “reasonable,” noting that she initially opposed a major welfare bill but later conceded it had produced some good results.

“There are a lot of things we don’t agree about, but we always got along quite well,” Haskins said of Blank.

Obama has long relied on his CEA for input that originates, at least somewhat, from academia. Goolsbee is leaving in September to return to a teaching job at the University of Chicago. The economist who led the CEA before him, Christina Romer, also left so she could go back to teaching, at Berkeley.

Blank and Auerbach both have academic roots. Blank was the dean of the public policy school at the University of Michigan, and Auerbach has taught economics since 1978. The other two members of the panel, Katharine Abraham and Carl Shapiro, also taught at universities.

That’s what sets the CEA apart from other Cabinet-level posts, economic observers say. “Traditionally, CEA has been the kind of first home for academics in economic policy,” said Bill Gale, a Brookings Institution fellow who recruited Blank at the liberal think tank before she went to the Commerce Department.

“Sometimes CEA is accused of being sort of out of touch or not politically sophisticated, but you need a voice in the discussion that is sort of focused on what is the right thing to do,” said Gale, a former senior staff economist on the CEA under President George H.W. Bush.

The CEA head also must be an effective spokesperson for Obama’s economic policies. Romer and Goolsbee routinely made the rounds on cable TV when Obama announced economic policies or monthly unemployment reports were released.

The White House would not say whom Obama has interviewed for the post. “We will decline to comment on speculation on any potential candidates until the president makes his decision,” spokeswoman Amy Brundage said in a statement.

Supporters for Blank and Auerbach characterized them both as potentially strong advocates for the president’s positions. Haskins described Blank as “brilliant” and “very clear in the way she talks.” Edlin said Auerbach is “quick on his feet” and has “sound and deep judgments about things.”

In late June, Goolsbee offered some advice for his replacement: “We have to grow, and we have to add jobs,” he told reporters on a conference call. “We have to add output, export more, invest more. We need broad-based growth in this country that gets away from the bubble-based … growth of the previous expansion.”